Package structure and antenna device using the same

ABSTRACT

An antenna device is provided. The antenna device includes a first substrate and a second substrate facing the first substrate. The first substrate includes an inner surface and an outer surface opposite the inner surface of the first substrate. The second substrate includes an inner surface and an outer surface opposite the inner surface of the second substrate. The antenna device also includes a die disposed between the first substrate and the second substrate, a redistribution layer disposed between the die and the inner surface of the second substrate, and an antenna unit electrically connected to the die via the redistribution layer. The antenna unit is arranged on at least one of the inner surface of the first substrate, the outer surface of the first substrate, the inner surface of the second substrate and the outer surface of the second substrate.

CROSS REFERENCE TO RELATED APPLICATIONS

This application claims the benefit of U.S. Provisional Application No.62/711,671, filed Jul. 30, 2018, and the entirety of which isincorporated by reference herein.

BACKGROUND Technical Field

Embodiments of the present disclosure relate to a package structure andan antenna device using the same, and in particular they relate to apackage structure for communication applications and an antenna deviceusing the same.

Description of the Related Art

Antennas are typically used for enabling wireless communication. In ahigh frequency application, such as 5th generation wireless systems(5G), satellites and automotive radars, these antennas need to havegood, adjustable directivity. Therefore, phase array antennas arecommonly used in high frequency applications.

However, traditional package structures for phase array antennas may notmeet demands for antenna devices in high frequency applications nowadaysbecause of their high manufacturing cost, high dielectric loss, andlarger areas.

SUMMARY

In accordance with some embodiments of the present disclosure, anantenna device is provided. The antenna device includes a firstsubstrate and a second substrate facing the first substrate. The firstsubstrate includes an inner surface and an outer surface opposite theinner surface of the first substrate. The second substrate includes aninner surface and an outer surface opposite the inner surface of thesecond substrate. The antenna device also includes a die disposedbetween the first substrate and the second substrate, a redistributionlayer disposed between the die and the inner surface of the secondsubstrate, and an antenna unit electrically connected to the die via theredistribution layer. The antenna unit is arranged on at least one ofthe inner surface of the first substrate, the outer surface of the firstsubstrate, the inner surface of the second substrate and the outersurface of the second substrate.

In accordance with some other embodiments of the present disclosure, apackage structure is provided. The package structure includes a firstsubstrate and a second substrate facing the first substrate, aredistribution layer disposed between the first substrate and the secondsubstrate, a die disposed between the redistribution layer and the firstsubstrate, a metal layer electrically connected to the redistributionlayer, and a sealant disposed between the first substrate and the secondsubstrate and surrounding the die.

BRIEF DESCRIPTION OF THE DRAWINGS

Aspects of the embodiments of the present disclosure are understood fromthe following detailed description when read with the accompanyingfigures. It should be noted that, in accordance with the standardpractice in the industry, various features are not drawn to scale. Infact, the dimensions of the various features may be arbitrarilyincreased or reduced for clarity of discussion.

FIG. 1 is a partial top view illustrating a package structure accordingto one embodiment of the present disclosure.

FIG. 2 is a partial cross-sectional view illustrating along line A-A inFIG. 1.

FIG. 3 is a partial cross-sectional view illustrating a packagestructure according to another embodiment of the present disclosure.

FIG. 4 is a partial cross-sectional view illustrating a packagestructure according to still another embodiment of the presentdisclosure.

DETAILED DESCRIPTION

The following disclosure provides many different embodiments, orexamples, for implementing different features of the subject matterprovided. Specific examples of components and arrangements are describedbelow to simplify the present disclosure. These are, of course, merelyexamples and are not intended to be limiting. For example, the formationof a first feature over or on a second feature in the description thatfollows may include embodiments in which the first and second featuresare formed in direct contact, and may also include embodiments in whichadditional features may be formed between the first and second features,such that the first and second features may not be in direct contact.

It should be understood that additional steps may be implemented before,during, or after the illustrated methods, and some steps might bereplaced or omitted in other embodiments of the illustrated methods.

Furthermore, spatially relative terms, such as “beneath,” “below,”“lower,” “on,” “above,” “upper” and the like, may be used herein forease of description to describe one element or feature's relationship toanother element(s) or feature(s) as illustrated in the figures. Thespatially relative terms are intended to encompass differentorientations of the device in use or operation in addition to theorientation depicted in the figures. The apparatus may be otherwiseoriented (rotated 45 degrees or at other orientations) and the spatiallyrelative descriptors used herein may likewise be interpretedaccordingly.

Unless otherwise defined, all terms (including technical and scientificterms) used herein have the same meaning as commonly understood by oneof ordinary skill in the art to which this disclosure belongs. It shouldbe understood that terms such as those defined in commonly useddictionaries should be interpreted as having a meaning that isconsistent with their meaning in the context of the relevant art andwill not be interpreted in an idealized or overly formal sense unlessexpressly so defined in the embodiments of the present disclosure.

FIG. 1 is a partial top view illustrating a package structure 100according to one embodiment of the present disclosure, and FIG. 2 is apartial cross-sectional view illustrating along line A-A in FIG. 1. Itshould be noted that not all components of the package structure 100 areshown in FIGS. 1-2, for the sake of brevity.

Referring to FIGS. 1 and 2, the package structure 100 includes a firstsubstrate 11 which is not shown in FIG. 1, a second substrate 12 facingthe first substrate 11, a redistribution layer (RDL) 20 disposed betweenthe first substrate 11 and the second substrate 12, a die 30 disposed onthe redistribution layer 20, a metal layer 41 electrically connected tothe redistribution layer 20, and a sealant 51 disposed between the firstsubstrate 11 and the second substrate 12 and surrounding the die 30.

As shown in FIG. 2, the first substrate 11 has an inner surface 11-1 andan outer surface 11-2 opposite the inner surface 11-1. The secondsubstrate 12 faces the first substrate 11, and similarly has an innersurface 12-1 and an outer surface 12-2 opposite the inner surface 12-1.Here, the first substrate 11 and the second substrate 12 may beexclusive of elemental semiconductor substrates (e.g., silicon,germanium), compound semiconductor substrates (e.g., tantalum carbide,gallium arsenide, indium arsenide or indium phosphide), alloysemiconductor substrates (e.g., silicon germanium, silicon germaniumcarbide, gallium arsenic phosphide or gallium indium phosphide), and soon.

In this embodiment, a material of one of the first substrate 11 and thesecond substrate 12 comprises at least one of glass, polyimide (PI),liquid-crystal polymer (LCP), polycarbonate (PC), polypropylene (PP),polyethylene terephthalate (PET) and other plastic or polymer materials.But the present disclosure is not limited thereto.

The redistribution layer 20 and the die 30 are both disposed between thefirst substrate 11 and the second substrate 12. As shown in FIGS. 1 and2, the redistribution layer 20 is disposed between the die 30 and theinner surface 12-1 of the second substrate 12. In other words, the die30 is disposed between the redistribution layer 20 and the firstsubstrate 11. The die 30 may be a bare die, and the redistribution layer20 may include a plurality of wire 21 and a plurality of insulatinglayers 22 that make the I/O pads 31 of integrated circuit of the die 30available in other locations. It should be noted that some components ofthe redistribution layer 20 in FIGS. 1 and 2 have been omitted here, forthe sake of brevity. That is, the structure of the redistribution layer20 should not be limited to the structure as shown in FIGS. 1 and 2.

In this embodiment, the metal layer 41 may be an antenna unit, so thatthe package structure 100 may be an antenna device. The metal layer (orthe antenna unit) 41 may be electrically connected to the die 30 via theredistribution layer 20. The die 30 may receive and/or transmit anelectronic-magnetic wave through the metal layer (or the antenna unit)41. As shown in FIG. 2, the metal layer (or the antenna unit) 41 isarranged on the outer surface 12-2 of the second substrate 12, but thepresent disclosure is not limited thereto. In some embodiments, themetal layer (or the antenna unit) 41 may be arranged on the outersurface 11-2 of the first substrate 11, the inner surface 11-1 of thefirst substrate 11, or the inner surface 12-1 of the second substrate12.

In this embodiment, the sealant 51 is disposed between the firstsubstrate 11 and the second substrate 12, and the sealant 51 surroundsthe die 30. The sealant 51 is used to keep the package structure 100sealed. In some embodiments, the sealant 51 may be a conductive sealant.

In this embodiment, the remaining space 15 between the first substrate11 and the second substrate 12 inside the sealant 51 is vacant. In someembodiments, the remaining space 15 between the first substrate 11 andthe second substrate 12 inside the sealant 51 may be filled with air,inert gases or low loss-tangent materials (such as fluoropolymer).Compared to traditional package structures using molding compounds,since the remaining space 15 between the first substrate 11 and thesecond substrate 12 inside the sealant 51 is vacant or filled with airor inert gases, the effects due to the different coefficients of thermalexpansion (CTE) between different components may be low. Therefore, thereliability of the package structure (or the antenna device) 100 may beeffectively enhanced.

Referring to FIGS. 1 and 2, in this embodiment, the package structure100 further includes a wire 43 disposed between the first substrate 11and the second substrate 12. In more detail, the wire 43 may be atransmission line which is electrically connected to the die 30 throughthe redistribution layer 20 and electrically connected to the metallayer 41. In the embodiment as shown in FIG. 2, at least one via hole 60penetrates the second substrate 12, and the wire (transmission line) 43passes through the via hole 60 to connect to the metal layer 41.However, the present disclosure is not limited thereto. In otherembodiments, if the metal layer 41 is disposed on the outer surface 11-2of the first substrate 11 (as shown in following FIG. 4), then the viahole 60 may penetrate the first substrate 11, and the wire (transmissionline) 43 passes through the via hole 60 to connect to the metal layer41.

In other words, the second substrate 12 (or the first substrate 11) mayinclude at least one via hole 60, and the wire 43 may pass through thevia hole 60 and electrically connect the metal layer (or the antennaunit) 41 to the redistribution layer 20 and the die 30.

Since the wire 43 passes through the second substrate 12 (or the firstsubstrate 11), the remaining space 15 (which is vacant or filled withair, inert gases or low loss-tangent materials), and the redistributionlayer 20 to electrically connect the metal layer (or the antenna unit)41 and the die 30, dielectric loss may be lower than in traditionalstructures (e.g., the antenna, antennas or phase array antenna madethrough printed circuit board (PCB)).

Moreover, the die 30 is sealed between the first substrate 11 and thesecond substrate 12 inside the sealant 51, so that the package structure100 may have better corrosion resistance than traditional packages.

Furthermore, the manufacturing cost of the antenna device using thepackage structure 100 according to the embodiments of the presentdisclosure may be lower than the manufacturing cost of the traditionalAiP (Antenna in Package).

It should be noted that the number and the location of the sealant 51and the number and the location of the spacers 70 may be different fromFIGS. 1 and 2, depending on demand.

In some embodiments, the package structure 100 may further include atleast one shielding layer 45 disposed on at least one of the innersurface 11-1 of the first substrate 11 and the inner surface 12-1 of thesecond substrate 12. For example, the shielding layers 45 are disposedon both the inner surface 11-1 of the first substrate 11 and the innersurface 12-1 of the second substrate 12 as shown in FIG. 2. Theshielding layer 45 may be another metal layer (e.g., a ground layer) forelectromagnetic shielding that blocks radio frequency electromagneticradiation.

In some embodiments, the package structure 100 may further include atleast one bonding element 80 disposed between first substrate 11 and thesecond substrate 12. For example, the package structure 100 includessolder balls disposed on the redistribution layer 20. These solder ballsare used as bonding elements 80 to electrically connect the conductivecomponent (e.g., the shielding layer 45) on the inner surface 11-1 ofthe first substrate 11 to the conductive component (e.g., the shieldinglayer 45) on the inner surface 12-1 of the second substrate 12.

It should be noted that the bonding element 80 is not limited to theform of solder balls as shown in FIGS. 1 and 2. Other suitable forms maybe applied in the package structure 100. Similarly, the number and thelocation of the bonding element 80 may be different from FIGS. 1 and 2,depending on demand.

In some embodiments, the package structure 100 may further include apotting compound layer 52 disposed outside the sealant 51. In moredetail, the potting compound layer 52 may be a second sealant, and thesealant 51 is disposed between the potting compound layer 52 and the die30. The potting compound layer 52 may provide better protection for thedie 30 between the first substrate 11 and the second substrate 12.

FIG. 3 is a partial cross-sectional view illustrating a packagestructure 101 according to another embodiment of the present disclosure.In this embodiment, the package structure 101 is used as an antennadevice. The package structure (or the antenna device) 101 includes afirst substrate 11 and a second substrate 12 facing the first substrate11. The package structure (or the antenna device) 101 also includes adie 30 disposed between the first substrate 11 and the second substrate12, a redistribution layer (RDL) 20 disposed between the die 30 and thesecond substrate 12, and a metal layer (or the antenna unit) 41electrically connected to the die via the redistribution layer 20.

As shown in FIG. 3, the first substrate 11 has an inner surface 11-1 andan outer surface 11-2 opposite the inner surface 11-1, and the secondsubstrate 12 has an inner surface 12-1 and an outer surface 12-2opposite the inner surface 12-1. In this embodiment, the metal layer (orthe antenna unit) 41 is arranged on the outer surface 12-2 of the secondsubstrate 12.

In this embodiment, the first substrate 11 and the second substrate 12may be glass substrates. However, the present disclosure is not limitedthereto. In other embodiments, the first substrate 11 and the secondsubstrate 12 may be polyimide (PI) substrates, liquid-crystal polymer(LCP) substrates, polycarbonate (PC) substrates, polypropylene (PP)substrates, polyethylene terephthalate (PET) substrates or other plasticor polymer substrates.

As shown in FIG. 3, the redistribution layer 20 and the die 30 are bothdisposed between the first substrate 11 and the second substrate 12, andsome portions of the redistribution layer 20 is disposed between the die30 and the inner surface 12-1 of the second substrate 12. In otherwords, the die 30 is disposed between the redistribution layer 20 andthe first substrate 11. The die 30 may be a bare die, and theredistribution layer 20 may include a plurality of wire 21 and aplurality of insulating layers 22 that make the I/O pads 31 ofintegrated circuit of the die 30 available in other locations.Similarly, some components of the redistribution layer 20 in FIG. 3 havebeen omitted here, for the sake of brevity. That is, the structure ofthe redistribution layer 20 should not be limited to the structure asshown in FIG. 3.

The metal layer (or the antenna unit) 41 may be electrically connectedto the die 30 via the redistribution layer 20. The die 30 may receiveand/or transmit an electronic-magnetic wave through the metal layer (orthe antenna unit) 41. As shown in FIG. 3, the metal layer (or theantenna unit) 41 is arranged on the outer surface 12-2 of the secondsubstrate 12, but the present disclosure is not limited thereto.

Moreover, the package structure (or the antenna device) 101 may includea sealant 51′ disposed between the first substrate 11 and the secondsubstrate 12, and the sealant 51′ surrounds the die 30. The differencebetween the package structure 101 and the package structure 100 is thata portion of the sealant 51′ (the sealant 51′ on the left side in FIG.3) in the package structure (or the antenna device) 101 is disposed onthe redistribution layer 20 as shown in FIG. 3, while the sealant 51 inthe package structure (or the antenna device) 100 is disposed outsidethe redistribution layer 20 as shown in FIG. 2.

In this embodiment, the remaining space 15 between the first substrate11 and the second substrate 12 inside the sealant 51′ is vacant. In someembodiments, the remaining space 15 between the first substrate 11 andthe second substrate 12 inside the sealant 51′ may be filled with air,inert gases or low loss-tangent materials (such as fluoropolymer).Compared to traditional package structures using molding compounds,since the remaining space 15 between the first substrate 11 and thesecond substrate 12 inside the sealant 51′ is vacant or filled with airor inert gases, the effects due to the different coefficients of thermalexpansion (CTE) between different components may be low. Therefore, thereliability of the package structure (or the antenna device) 101 may beeffectively enhanced.

Referring to FIG. 3, in this embodiment, the package structure 101further includes a wire 43 disposed between the first substrate 11 andthe second substrate 12. In more detail, the wire 43 may be atransmission line which is electrically connected to the die 30 throughthe redistribution layer 20 and electrically connected to the metallayer 41. In the embodiment as shown in FIG. 3, at least one via hole 60penetrates the second substrate 12, and the wire (transmission line) 43passes through the via hole 60 to connect to the metal layer 41.However, the present disclosure is not limited thereto.

In other words, the second substrate 12 may include at least one viahole 60, and the wire 43 may pass through the via hole 60 andelectrically connect the metal layer (or the antenna unit) 41 to theredistribution layer 20 and the die 30.

Since the wire 43 passes through the second substrate 12, the remainingspace 15 (which is vacant or filled with air, inert gases or lowloss-tangent materials), and the redistribution layer 20 to electricallyconnect the metal layer (or the antenna unit) 41 and the die 30,dielectric loss may be lower than in traditional structures (e.g., theantenna made through printed circuit board (PCB)).

Moreover, the die 30 is sealed between the first substrate 11 and thesecond substrate 12 inside the sealant 51′, so that the packagestructure 101 may have better corrosion resistance than traditionalpackages.

Furthermore, the manufacturing cost of the antenna device using thepackage structure 101 according to the embodiments of the presentdisclosure may be lower than the manufacturing cost of the traditionalAiP (Antenna in Package).

In this embodiment, the package structure 101 may further include aplurality of spacers 70′ disposed between the first substrate 11 and thesecond substrate 12 as shown in FIG. 3. The spacers 70′ may be used tomaintain the gap between the first substrate 11 and the second substrate12. For example, the spacers 70′ may be cell gap spacers, such as a ballspacer, a photo spacer, glass fiber, or another suitable spacer.

In this embodiment, the package structure 101 may further includeshielding layers 45 disposed on both the inner surface 11-1 of the firstsubstrate 11 and the inner surface 12-1 of the second substrate 12 asshown in FIG. 3. Each of the shielding layers 45 may be another metallayer (e.g., a ground layer) for electromagnetic shielding that blocksradio frequency electromagnetic radiation.

In this embodiment, the package structure 101 may further include atleast one bonding element 80′ disposed between first substrate 11 andthe second substrate 12. For example, the package structure 101 includessolder balls disposed on the redistribution layer 20. These solder ballsare used as bonding elements 80′ to electrically connect the conductivecomponent (e.g., the shielding layer 45) on the inner surface 11-1 ofthe first substrate 11 to the conductive component (e.g., the shieldinglayer 45) on the inner surface 12-1 of the second substrate 12.

Moreover, the number and the location of the spacers 70′ and the numberand the location of the bonding element 80′ in the package structure 101as shown in FIG. 3 are different from the number and the location of thespacers 70 and the number and the location of the bonding element 80 inthe package structure 100 as shown in FIG. 2.

Similarly, the package structure 101 may further include a pottingcompound layer 52 disposed outside the sealant 51′. In more detail, thepotting compound layer 52 may be a second sealant, and the sealant 51′is disposed between the potting compound layer 52 and the die 30. Thepotting compound layer 52 may provide better protection for the die 30between the first substrate 11 and the second substrate 12.

FIG. 4 is a partial cross-sectional view illustrating a packagestructure 102 according to still another embodiment of the presentdisclosure. Referring to FIG. 4, the package structure 102 includes afirst substrate 11 and a second substrate 12 opposite each other, aredistribution layer (RDL) 20 disposed between the first substrate 11and the second substrate 12, a die 30 disposed on the redistributionlayer 20, a metal layer 41′ electrically connected to the redistributionlayer 20, and a sealant 51 disposed between the first substrate 11 andthe second substrate 12 and surrounding the die 30.

As shown in FIG. 4, the first substrate 11 has an inner surface 11-1 andan outer surface 11-2 opposite the inner surface 11-1. The secondsubstrate 12 faces the first substrate 11, and similarly has an innersurface 12-1 and an outer surface 12-2 opposite the inner surface 12-1.

In this embodiment, the first substrate 11 and the second substrate 12may be glass substrates. However, the present disclosure is not limitedthereto. In other embodiments, the first substrate 11 and the secondsubstrate 12 may be polyimide (PI) substrates, liquid-crystal polymer(LCP) substrates, polycarbonate (PC) substrates, polypropylene (PP)substrates, polyethylene terephthalate (PET) substrates or other plasticor polymer substrates.

The redistribution layer 20 and the die 30 are both disposed between thefirst substrate 11 and the second substrate 12. As shown in FIG. 4, theredistribution layer 20 is disposed between the die 30 and the innersurface 12-1 of the second substrate 12. In other words, the die 30 isdisposed between the redistribution layer 20 and the first substrate 11.The die 30 may be a bare die, and the redistribution layer 20 mayinclude a plurality of wire 21 and a plurality of insulating layers 22that make the I/O pads 31 of integrated circuit of the die 30 availablein other locations. It should be noted that some components of theredistribution layer 20 in FIG. 4 have been omitted here, for the sakeof brevity. That is, the structure of the redistribution layer 20 shouldnot be limited to the structure as shown in FIG. 4.

In this embodiment, the metal layer 41′ may be an antenna unit, so thatthe package structure 102 may be an antenna device. The metal layer (orthe antenna unit) 41′ may be electrically connected to the die 30 viathe redistribution layer 20. The die 30 may receive and/or transmit anelectronic-magnetic wave through the metal layer (or the antenna unit)41′. The difference between the package structure 102 and the packagestructure 100 is that the metal layer 41′ in the package structure 102is disposed on the outer surface 11-2 of the first substrate 11 as shownin FIG. 4, while the metal layer 41 in the package structure 100 isdisposed on the outer surface 12-2 of the second substrate 12 as shownin FIG. 2.

In this embodiment, the sealant 51 is disposed between the firstsubstrate 11 and the second substrate 12, and the sealant 51 surroundsthe die 30. The sealant 51 is used to keep the package structure 100sealed. In some embodiments, the sealant 51 may be a conductive sealant.

In this embodiment, the remaining space 15′ between the first substrate11 and the second substrate 12 inside the sealant 51 is filled with lowloss-tangent materials (such as fluoropolymer).

Referring to FIG. 4, in this embodiment, the package structure 102further includes a wire 43′ disposed between the first substrate 11 andthe second substrate 12. In more detail, the wire 43′ may be atransmission line which is electrically connected to the die 30 throughthe redistribution layer 20 and electrically connected to the metallayer 41′. In the embodiment as shown in FIG. 4, at least one via hole60′ penetrates the first substrate 11, and the wire (transmission line)43′ passes through the via hole 60′ to connect to the metal layer 41′.

In other words, the first substrate 11 may include at least one via hole60′, and the wire 43′ may pass through the via hole 60′ and electricallyconnect the metal layer (or the antenna unit) 41′ to the redistributionlayer 20 and the die 30.

Since the wire 43′ passes through the first substrate 11, the remainingspace 15′ (which is filled with low loss-tangent materials), and theredistribution layer 20 to electrically connect the metal layer (or theantenna unit) 41′ and the die 30, dielectric loss may be lower than intraditional structures (e.g., the antenna made through printed circuitboard (PCB)).

Moreover, the die 30 is sealed between the first substrate 11 and thesecond substrate 12 inside the sealant 51, so that the package structure102 may have better corrosion resistance than traditional packages.

Furthermore, the manufacturing cost of the antenna device using thepackage structure 102 according to the embodiments of the presentdisclosure may be lower than the manufacturing cost of the traditionalAiP (Antenna in Package).

In some embodiments, the package structure 102 may further include aplurality of spacers 70 disposed between the first substrate 11 and thesecond substrate 12. The spacers 70 may be used to maintain the gapbetween the first substrate 11 and the second substrate 12. For example,the spacers 70 may be cell gap spacers, such as a ball spacer, a photospacer, glass fiber, or another suitable spacer.

In some embodiments, the package structure 102 may further includeshielding layers 45 disposed on both the inner surface 11-1 of the firstsubstrate 11 and the inner surface 12-1 of the second substrate 12 asshown in FIG. 4. Each of the shielding layers 45 may be another metallayer (e.g., a ground layer) for electromagnetic shielding that blocksradio frequency electromagnetic radiation.

In some embodiments, the package structure 102 may further include atleast one bonding element 80 disposed between first substrate 11 and thesecond substrate 12. For example, the package structure 102 includessolder balls disposed on the redistribution layer 20. These solder ballsare used as bonding elements 80 to electrically connect the conductivecomponent (e.g., the shielding layer 45) on the inner surface 11-1 ofthe first substrate 11 to the conductive component (e.g., the shieldinglayer 45) on the inner surface 12-1 of the second substrate 12.

In some embodiments, the package structure 102 may further include apotting compound layer 52 disposed outside the sealant 51. In moredetail, the potting compound layer 52 may be a second sealant, and thesealant 51 is disposed between the potting compound layer 52 and the die30. The potting compound layer 52 may provide better protection for thedie 30 between the first substrate 11 and the second substrate 12.

It should be noted that the antenna device is used as an example in theembodiments described above, but the present disclosure is not limitedthereto. In some embodiments, the package structure 100 (or 101, 102)may be used in other devices for communication application.

In summary, the package structure (or the antenna device) of theembodiments of the present disclosure includes the first substrate andthe second substrate, and the remaining space between the firstsubstrate and the second substrate inside the sealant is vacant orfilled with air or inert gases, and thus the effects due to thedifferent coefficients of thermal expansion (CTE) between differentcomponents may be low. Furthermore, in the package structure (or theantenna device) of the embodiments of the present disclosure, the wire(transmission line) passes through one of the first substrate and thesecond substrate, the remaining space (which is vacant or filled withair, inert gases or low loss-tangent materials), and the redistributionlayer to electrically connect the metal layer (or the antenna unit) andthe die, and thus the dielectric loss may be effectively reduced.Furthermore, the die in the package structure (or the antenna device) ofthe embodiments of the present disclosure is sealed between the firstsubstrate and the second substrate inside the sealant (and the sealantmay be inside the potting compound layer in some embodiments), and thusthe package structure (or the antenna device) may have better corrosionresistance and the reliability of the package structure (or the antennadevice) may be effectively enhanced.

The foregoing outlines features of several embodiments so that thoseskilled in the art may better understand the aspects of the presentdisclosure. Those skilled in the art should appreciate that they mayreadily use the present disclosure as a basis for designing or modifyingother processes and structures for carrying out the same purposes and/orachieving the same advantages of the embodiments introduced herein.Those skilled in the art should also realize that such equivalentconstructions do not depart from the spirit and scope of the presentdisclosure, and that they may make various changes, substitutions, andalterations herein without departing from the spirit and scope of thepresent disclosure. Therefore, the scope of protection should bedetermined by the claims. In addition, although some embodiments of thepresent disclosure are disclosed above, they are not intended to limitthe scope of the present disclosure.

Reference throughout this specification to features, advantages, orsimilar language does not imply that all of the features and advantagesthat may be realized with the present disclosure should be or are in anysingle embodiment of the disclosure. Rather, language referring to thefeatures and advantages is understood to mean that a specific feature,advantage, or characteristic described in connection with an embodimentis included in at least one embodiment of the present disclosure. Thus,discussions of the features and advantages, and similar language,throughout this specification may, but do not necessarily, refer to thesame embodiment.

Furthermore, the described features, advantages, and characteristics ofthe disclosure may be combined in any suitable manner in one or moreembodiments. One skilled in the relevant art will recognize, in light ofthe description herein, that the disclosure can be practiced without oneor more of the specific features or advantages of a particularembodiment. In other instances, additional features and advantages maybe recognized in certain embodiments that may not be present in allembodiments of the disclosure.

What is claimed is:
 1. An antenna device, comprising: a first substrate,wherein the first substrate comprises an inner surface and an outersurface opposite the inner surface of the first substrate; a secondsubstrate facing the first substrate, wherein the second substratecomprises an inner surface and an outer surface opposite the innersurface of the second substrate; a die disposed between the firstsubstrate and the second substrate; a redistribution layer disposedbetween the die and the inner surface of the second substrate; and anantenna unit electrically connected to the die via the redistributionlayer; wherein the antenna unit is arranged on at least one of the innersurface of the first substrate, the outer surface of the firstsubstrate, the inner surface of the second substrate and the outersurface of the second substrate.
 2. The antenna device of claim 1,comprising: a first sealant disposed between the first substrate and thesecond substrate; wherein the first sealant surrounds the die.
 3. Theantenna device of claim 2, comprising: a second sealant, wherein thefirst sealant is disposed between the second sealant and the die.
 4. Theantenna device of claim 2, comprising: a plurality of spacers disposedbetween the first substrate and the second substrate.
 5. The antennadevice of claim 2, wherein a remaining space between the first substrateand the second substrate inside the first sealant is vacant or filledwith air, inert gases or low loss-tangent materials.
 6. The antennadevice of claim 1, comprising: a wire; wherein the second substratecomprises at least one via hole, and the wire passes through the viahole and is electrically connected the antenna unit and theredistribution layer.
 7. The antenna device of claim 1, furthercomprising: a wire; wherein the first substrate comprises at least onevia hole, and the wire passes through the via hole and is electricallyconnected the antenna unit and the redistribution layer.
 8. The antennadevice of claim 1, comprising: at least one shielding layer disposed onat least one of the inner surface of the first substrate and the innersurface of the second substrate.
 9. The antenna device of claim 1,wherein a material of one of the first substrate and the secondsubstrate comprises at least one of glass, polyimide, liquid-crystalpolymer, polycarbonate, polypropylene, and polyethylene terephthalate.10. A package structure, comprising: a first substrate; a secondsubstrate facing the first substrate; a redistribution layer disposedbetween the first substrate and the second substrate; a die disposedbetween the redistribution layer and the first substrate; a metal layerelectrically connected to the redistribution layer; and a sealantdisposed between the first substrate and the second substrate andsurrounding the die.
 11. The package structure of claim 10, wherein aremaining space between the first substrate and the second substrateinside the sealant is vacant or filled with air, inert gases or lowloss-tangent materials.
 12. The package structure of claim 10,comprising: a transmission line disposed between the first substrate andthe second substrate; wherein the transmission line is electricallyconnected to the die through the redistribution layer, and thetransmission line is electrically connected to the metal layer.
 13. Thepackage structure of claim 12, comprising: at least one via holepenetrating one of the first substrate and the second substrate; whereinthe transmission line passes through the at least one via hole toconnect to the metal layer.
 14. The package structure of claim 10,comprising: a plurality of spacers disposed between the first substrateand the second substrate.
 15. The package structure of claim 10,comprising: at least one shielding layer disposed on at least one innersurface of the first substrate and the second substrate.
 16. The packagestructure of claim 10, comprising: at least one bonding element disposedbetween the first substrate and the second substrate.
 17. The packagestructure of claim 10, wherein the metal layer is disposed on an innersurface of one of the first substrate and the second substrate or on anouter surface of one of the first substrate and the second substrate.18. The package structure of claim 10, wherein the metal layer is anantenna unit.
 19. The package structure of claim 10, wherein a materialof one of the first substrate and the second substrate comprises atleast one of glass, polyimide, liquid-crystal polymer, polycarbonate,polypropylene, and polyethylene terephthalate.
 20. The package structureof claim 10, comprising: a potting compound layer disposed outsidesealant.